Something is wrong with Kentucky fried!

I have a rooster that got a few months ago he might be about 2 years old. I went to feed everyone today and he was sitting in front of the coop. It was raining and he was just siting out there not moving but his eyes were open. I picked him up and he didn't fight it at all. he can move his legs and stand. if i put water on his beak he will drink. if i hold him he goes to sleep. he seems alittle skinny and his crop feels empty. he has no injuries that i can see. all my other chickens and ducks are fine. I put him in the garage with food and water. his eyes are clear. there is no discharge from his nose or mouth and his comb is still red. What could be wrong with him?
P.S. he was already named when i got him lol.

I would give him Sulmet and an antibiotic simutaneously... Cocci or a toxin... follow the directions and while doing this give him egg bread and soft food.... after you finish the round of medicine...use rooster booster... hopefully he will snap out of it...

The rain creates and overgrowth of Cocci and he just is sick from it....Treat him immediatly...

egg bread is bread made with only eggs for liquid (at least the ones i make) im sure you can google about a million recipes. ive been dealing with a bit of the same except most of mine also have a respitory problem too, i lost three, i believe to a combination of lice, worms, dehydration, and the colds. that said i would check for lice first, then make sure hes drinking. after that, if you dont want to medicate for worms, and he will eat, stick some fresh RAW pumpkin seeds in a food process and mix it with his food, or feed it solely for a treat one day, it wont completely wipe out all the worms like a medication, but it will help remove some.. GOODLUCK

im sorry he passed, all three of mine that were showing close to the same symptoms passed as well, i think its because they do theyre best to act fine until they just cant take it anymore and start to go, and by that time, they are to far gone to help...